<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>布局技巧_1</title>
    <style>
        .outter{
          width: 400px;
          height: 400px;
          background-color: gray;
          overflow: hidden;
        }
        .inner{
          width: 100px;
          height: 100px;
          background-color: skyblue;
          margin: 0 auto;
          margin-top: 150px;
          text-align: center;
          line-height: 100px;
        }
    </style>
  </head>
  <body>
    <div class="outter">
      <div class="inner">inner</div>
    </div>
  </body>
</html>
